Poly(arylene thioether-ketone) copolymer and production process thereof

ABSTRACT

Disclosed herein are a poly(arylene thioether-ketone) copolymer comprising (A) at least one poly(arylene thioether-ketone) segment having predominant recurring units of the formula ##STR1## wherein the --CO-- and --S-- are in the para position to each other and (B) at least one poly(arylene thioether) segment having predominant recurring units of the formula ##STR2## (a) the ratio of the total amount of the poly(arylene thioether) segment (B) to the total amount of the poly(arylene thioether-ketone) segment (A) ranging from 0.05 to 5 by weight, (b) the number-average polymerization degree of the poly(arylene thioether) segment (B) being higher than 1 but lower than 10, and (c) said copolymer having a melt viscosity of 2-100,000 poises as measured at 350° C. and a shear rate of 1,200/sec as well as a production process of the poly(arylene thioether-ketone) copolymer.

This application is a division of application Ser. No. 07/686,978, filedApr. 18, 1991, now U.S. Pat. No. 5,288,815.

FIELD OF THE INVENTION

This invention relates to crystalline poly(arylene thioether-ketone)copolymers uniform in composition and excellent in heat resistance, meltstability, processability and handling properties, and more specificallyto novel copolymers containing at least one poly(arylenethioether-ketone) segment [hereinafter abbreviated as "PTK segment (A)"or merely "segment (A)"] having predominant recurring units of theformula ##STR3## and at least one poly(arylene thioether) segment[hereinafter abbreviated as "PATE segment (B)" or merely "segment (B)"]having predominant recurring units of the formula ##STR4## and also to aprocess for the production thereof.

This invention is also concerned with a process for economicallyproducing crystalline aromatic ketone copolymers by using inexpensivecomonomers and polymerization solvent.

BACKGROUND OF THE INVENTION

In the fields of the electronic and electrical industry and theautomobile, aircraft and space industries, there is a strong demand inrecent years for crystalline thermoplastic resins having high heatresistance of about 300° C. or higher in terms of melting point andmoreover easy melt processability. Polyether ketones having predominantrecurring units of the following structural formula [I] or [II]:##STR5## were discussed [Polymer, 21, 577 (1980)].

These polyether ketones have excellent heat resistance and mechanicalstrength. However, they use expensive fluorine-containing monomers andutilize, as a solvent, an aromatic sulfone which is costly upon itsseparation and purification from the resulting polymers. Theirproduction process thus involves many disadvantages in its industrialuse (Japanese Patent Publication No. 22938/1982).

Besides, as poly(arylene thioether-ketone) type polymers, there havebeen proposed polymers having predominant recurring units of thefollowing structural formula [III ], [IV], [V] or [VI ]: ##STR6##

The poly(arylene thioether-ketones) (hereinafter abbreviated as "PTKs")having the predominant recurring units of the structural formula [III]have excellent heat resistance, but involve a problem that they havepoor heat stability upon melting (hereinafter called "melt stability")(Japanese Patent Laid-Open Nos. 58435/1985 and 124/1989). The polymershaving the predominant recurring units of the structural formulae [IV]and [V], respectively, are not suitable for industrial productionbecause they must use particular polymerization solvents and monomers(Japanese Patent Laid-Open Nos. 200127/1986, 197634/1986 and27434/1987). The poly(arylene thioether ketone ketones) (hereinafterabbreviated as "PTKKs") having the predominant recurring units of thestructural formula [VI] have a melting point as extremely high as about410° C. Their melt processing temperature are high accordingly, so thatthey tend to loss their crystallinity or to undergo cross-linking and/orcarbonization, resulting in a rapid increase in melt viscosity, upontheir melt processing.

In addition, since PTKs and PTKKs contain ketone groups in theirrecurring units, they are poor in solvent resistance and moistureabsorption resistance, so that their application fields asheat-resistant resins are unavoidably limited. PTKs and PTKKs aregenerally obtained as fine powders. This has led to an additionalproblem upon their production such that they show poor handlingproperties in their collection step after polymerization, especially infiltration, washing, drying and transportation. Still further problemshave also arisen such as poor metering property upon melt processing andoccurrence of blocking in hoppers or the like.

On the other hand, for example, poly(p-phenylene thioether) as apoly(arylene thioether) (hereinafter abbreviated as "PATE") is used ashigh-performance engineering plastics having excellent heat resistanceand solvent resistance. This polymer is obtained by reactingdichlorobenzene, which is very cheap and industrially available, withsodium sulfide (U.S. Pat. No. 3,919,177). However, its crystallinemelting point is about 285° C. and its glass transition point (Tg) isalso as low as about 85° C. There is thus a demand for development ofpolymers having a higher melting point and a higher Tg.

In order to solve the above problem, there has also been proposedcopolymers in which arylene thioether units and sulfone units of theformula ##STR7## and/or ketone units of the formula ##STR8## areintroduced at random therein (Japanese Patent Publication No.5100/1984).

It is however impossible to obtain polymers having satisfactoryuniformity in composition, heat resistance and/or melt stability by theprior art process in which a dihalobenzene and a dihalogenated aromaticcompound activated by the ketone group or sulfone group are reactedtogether with an alkali metal sulfide in a polar organic solvent tocopolymerize them, because their reactivity and chemical stability in apolymerization system are different from each other. Namely, theresultant random copolymers tend to have lower crystallinity and poorerheat resistance and mechanical properties as the proportion of thearylene thioether units decreases, in particular, to 90 mole % or less.

It has been proposed to react an aromatic thioether with phosgene or anaromatic dicarboxylic acid dihalide in the presence of a Lewis acid in anon-polar solvent, thereby obtaining polymers having respectivepredominant recurring units of the following structural formulae [VII]and [VIII] (Japanese Patent Laid-Open Nos. 104126/1985 and 120720/1985):##STR9## However, the resulting polymers were accompanied by problemsthat they had a low degree of polymerization and poor melt stability,and undergo gelation easily.

OBJECTS AND SUMMARY OF THE INVENTION

An object of this invention is to provide polymers with improvedprocessability, handling properties and solvent resistance whileretaining the excellent properties, such as heat resistance andcrystallinity, of the aforementioned melt-stable PTKs as much aspossible. Another object of this invention is to provide a process foreconomically producing aromatic ketone copolymers having suchproperties.

With a view toward improving the processability of a PTK, the presentinventors first of all attempted to lower the melting point, i.e.,processing temperature of the PTK by random copolymerization of itsmonomer with monomers of a kind different from the first-mentionedmonomer. Namely, 4,4'-dihalobenzophenone was used as a comonomer andcopolymerized with dihalobenzene. However, the resultant randomcopolymers tended to have lower crystallinity and heat resistance andpoorer melt stability as the proportions of the dihalobenzenesincreased. Further, 4,4'-dihalo-benzophenones have been activated by theketone group and have far higher reactivity compared withdihalobenzenes. They hence have extremely poor copolymerizability withdihalobenzenes.

The present inventors then attempted to produce a PTK-PATE copolymer inwhich a PATE having recurring units of the formula ##STR10## isincorporated as segments in the chain of a PTK. As a result, it has beenfound that a poly(arylene thioether-ketone) copolymer having excellentprocessability and high crystallinity can be obtained by using as anoligomer a PATE, which has a particular number-average polymerizationdegree and contains at least one terminal thiolate group and/or thiolgroup as a reactive terminal group, and reacting the PATE oligomer witha 4,4'-dihalo-benzophenone under specific conditions in an organic amidesolvent.

It has also been found that a copolymer similar to the above-describedcopolymer can be obtained by reacting the PATE oligomer with a PTKoligomer under specific conditions. It has also been revealed that eachof these copolymers can be obtained as granules having good handlingproperties from its polymerization system by a conventional collectionmethod.

The present invention has been brought to completion on the basis ofthese findings.

In one aspect of this invention, there is thus provided a poly(arylenethioether-ketone) copolymer comprising (A) at least one poly(arylenethioether-ketone) segment having predominant recurring units of theformula ##STR11## wherein the --CO-- and --S-- are in the para positionto each other and (B) at least one poly(arylene thioether) segmenthaving predominant recurring units of the formula ##STR12## and havingthe following properties (a)-(c): (a) the ratio of the total amount ofthe poly(arylene thioether) segment (B) to the total amount of thepoly(arylene thioether-ketone) segment (A) ranging from 0.05 to 5 byweight,

(b) the number-average polymerization degree of the poly(arylenethioether) segment (B) being higher than 1 but lower than 10, and

(c) said copolymer having a melt viscosity of 2-100,000 poises asmeasured at 350° C. and a shear rate of 1,200/sec.

In another aspect of this invention, there is also provided a processfor the production of a poly(arylene thioether-ketone) copolymercomprising (A) at least one poly(arylene thioether-ketone) segment and(B) at least one poly(arylene thioether) segment, which comprises atleast the following two steps:

i) heating in the presence of water an organic amide solvent containinga dihalogenated aromatic compound, which consists principally of adihalobenzene, and an alkali metal sulfide, whereby a poly(arylenethioether) oligomer having predominant recurring units of the formula##STR13## and at least one terminal thiolate group is synthesized, andii) mixing the oligomer, which has been obtained in the step i), with adihalogenated aromatic compound consisting principally of at least onedihalobenzophenone selected from 4,4'-dichlorobenzophenone and4,4'-dibromobenzophenone, and optionally, an alkali metal sulfide, anorganic amide solvent and/or water, and heating the resultant mixture toform a poly(arylene thioether-ketone) segment having predominantrecurring units of the formula ##STR14## wherein the --CO-- and --S--are in the para position to each other, thereby forming the copolymer;

said first and second steps i) and ii) being conducted under thefollowing conditions (a)-(f):

(a) in the first step i), the ratio of the water content to the amountof the charged organic amide solvent being 0.1-15 (mol/kg), the ratio ofthe amount of the charged dihalogenated aromatic compound to the amountof the charged alkali metal sulfide being 0.3-0.9 (mol/mol), and thepolymerization being conducted in such a manner that the resultingpoly(arylene thioether) oligomer has at least one terminal thiolategroup and its number-average polymerization degree becomes higher than 1but lower than 10,

(b) in the second step ii), the ratio of the water content to the amountof the charged organic amide solvent being controlled within a range of0.1-15 (mol/kg),

(c) in the second step ii), the ratio of the total amount of the chargeddihalogenated aromatic compound, said total amount being the amount ofthe whole dihalogenated aromatic compounds including the dihalobenzeneand the dihalobenzophenone, to the total amount of the charged alkalimetal sulfide, said latter total amount being the total amount of thealkali metal sulfide charged in the first step i) and that optionallycharged in the second step ii), being controlled within a range of0.95-1.2 (mol/mol),

(d) the ratio of the charged amount of the dihalogenated aromaticcompound consisting principally of the dihalobenzene in the step i) tothe charged amount of the dihalogenated aromatic compound consistingprincipally of the dihalobenzophenone in the step ii) being controlledwithin a range of 0.1-10 (mol/mol),

(e) the reaction of the second step ii) being conducted within atemperature range of 150°-300° C. with the proviso that the reactiontime at 210° C. and higher is not longer than 10 hours, and

(f) in the second step ii), the reaction being conducted until the meltviscosity of the resulting copolymer becomes 2-100,000 poises asmeasured at 350° C. and a shear rate of 1,200/sec.

In a further aspect of this invention, there is also provided a processfor the production of a poly(arylene thioether-ketone) copolymercomprising (A) at least one poly(arylene thioether-ketone) segment and(B) at least one poly(arylene thioether) segment, which comprises atleast the following three steps:

i) heating in the presence of water an organic amide solvent containinga dihalogenated aromatic compound, which consists principally of adihalobenzene, and an alkali metal sulfide, whereby a poly(arylenethioether) oligomer having predominant recurring units of the formula##STR15## and at least one terminal thiolate group is synthesized, ii)heating in the presence of water an organic amide solvent containing adihalogenated aromatic compound, which consists principally of at leastone dihalobenzophenone selected from 4,4'-dichlorobenzophenone and4,4'-dibromobenzophenone, and an alkali metal sulfide, whereby apoly(arylene thioether-ketone) oligomer having predominant recurringunits of the formula ##STR16## wherein the --CO-- and --S-- are in thepara position to each other, and terminal halogen atoms is synthesized,and

iii) mixing and reacting the poly(arylene thioether) oligomer, which hasbeen obtained in the step i), with poly(arylene thioether-ketone)oligomer obtained in the step ii) and optionally, water;

said first through third steps i)-iii) being conducted under thefollowing conditions (a)-(g):

(a) in the first step i), the ratio of the water content to the amountof the charged organic amide solvent being 0.1-15 (mol/kg), the ratio ofthe amount of the charged dihalogenated aromatic compound to the amountof the charged alkali metal sulfide being 0.3-0.9 (mol/mol), and thepolymerization being conducted until the number-average polymerizationdegree of the poly(arylene thioether) oligomer becomes higher than 1 butlower than 10,

(b) in the second step ii), the ratio of the water content to the amountof the charged organic amide solvent being controlled within a range of0.1-15 (mol/kg) and the reaction being conducted within a temperaturerange of 60°-300° C. with the proviso that the reaction time at 210° C.and higher is not longer than 10 hours,

(c) in the third step iii), the ratio of the water content to the amountof the charged organic amide solvent being 0.1-15 (mol/kg),

(d) in the third step iii), the ratio of the total amount of the chargeddihalogenated aromatic compound, said total amount being the amount ofthe whole dihalogenated aromatic compounds including the dihalobenzeneand the dihalobenzophenone, to the total amount of the charged alkalimetal sulfide, said latter total amount being the total amount of thealkali metal sulfide charged in the first step i) and that charged inthe second step ii), being controlled within a range of 0.95-1.2(mol/mol),

(e) the ratio of the charged amount of the dihalogenated aromaticcompound consisting principally of the dihalobenzene in the step i) tothe charged amount of the dihalogenated aromatic compound consistingprincipally of the dihalobenzophenone in the step ii) being controlledwithin a range of 0.1-10 (mol/mol),

(f) the reaction of the third step iii) being conducted within atemperature range of 150°-300° C. with the proviso that the reactiontime at 210° C. and higher is not longer than 10 hours, and

(g) in the third step iii), the reaction being conducted until the meltviscosity of the resulting copolymer becomes 2-100,000 poises asmeasured at 350° C. and a shear rate of 1,200/sec.

DETAILED DESCRIPTION OF THE INVENTION

Features of the present invention will hereinafter be described indetail.

Poly(Arylene Thioether-Ketone) Copolymer Chemical Structure of Copolymer

The poly(arylene thioether-ketone) copolymers according to the presentinvention are copolymers comprising (A) at least one PTK segment havingpredominant recurring units of the formula ##STR17## wherein the --CO--and --S-- are in the para position to each other and (B) at least onePATE segment having predominant recurring units of the formula ##STR18##

The PTK segment (A) and the PATE segment (B) contain respectively theabove-described recurring units in proportions of at least 50 wt. %,preferably at least 70 wt. %, particularly preferably at least 80 wt. %.By the way, as the recurring unit of the segment (B), the recurring unitof the formula ##STR19## is preferred because it can afford copolymersexcellent especially from the viewpoint of crystallinity, meltstability, heat resistance, mechanical properties, solvent resistance,moisture absorption resistance and the like.

The copolymer of the present invention can have a desired structurecontaining both segments in an alternate order, such as ##STR20## mbeing 0 or an integer of 1 or greater or ##STR21## n being 0 or aninteger of 1 or greater.

It is however required that the weight ratio of the total amount ofsegments (B) to the total amount of segments (A) be within a range of0.05-5, preferably 0.1-4, more preferably 0.15-3.

The segment (A) serves to impart high degree of heat resistance andcrystallinity to the copolymer. On the other hand, the segment (B)contributes to the reduction of the processing temperature and thegranulation while maintaining the high crystallinity. Therefore,copolymers in each of which the weight ratio of the total amount ofsegments (B) to the total amount of segments (A) is at least 0.05 butlower than 1, preferably at least 0.1 but lower than 1 featureparticularly good heat resistance and high crystallinity. Ratios in arange of 1-5, preferably 1-4 give copolymers excellent especially inprocessability while retaining excellent crystallinity. However, anyweight ratios of the total amount of segments (B) to the total amount ofsegments (A) lower than 0.05 are too low to achieve any sufficientreduction in processing temperature or the formation into granules. Tothe contrary, any ratios higher than 5 lead to a substantial reductionin heat resistance and disturb the balancing between heat resistance andprocessability. Ratios outside the above range are therefore notpreferred.

It is essential for the sediment (B) to have a number-averagepolymerization degree higher than 1 but lower than 10, preferably, in arange of 2-9, more preferably, in a range of 3-8. When the length ofeach segment in the copolymer according to the present invention isshortened, the melting point becomes sharp, and the uniformity incomposition becomes high, so that preferred processability and physicalproperties can easily be achieved.

If the number-average polymerization degree of the segment (B) is notlower than 10, the resulting copolymer becomes similar to a blockcopolymer, so that it has physical properties characteristic of bothPATE and PTK, for example, melting points corresponding to those thereofand requires a temperature higher than that of the copolymer accordingto the present invention upon its forming or molding. Therefore, itsmelt processing temperature becomes higher, so that melt processingfacilities for high-temperature processing are required. Further, astringent temperature control is required to perform melt processingwithout deterioration by heat. Furthermore, since each segment is long,the composition distribution of the copolymer becomes widercorrespondingly. Polymerization degrees outside the above range aretherefore not preferred.

Besides, a segment (B) having a number-average polymerization degree of1, i.e. ##STR22## M being an alkali metal, is difficult to produce.

Incidentally, the number-average polymerization degree of the PATEsegment in this invention is determined by gel permeation chromatography(GPC) at a stage of the PATE oligomer. Measuring conditions are asfollows:

Column: SHODEX AT80M/S, two columns in series

Solvent: α-chloronaphthalene

Flow rate: 0.7 ml/min

Temperature: 220° C.

Sample concentration: 0.05 wt. %

Charged amount: 200 μl

Detector: flame ionization detector (FID)

Calibration of molecular weight: standard poly (styrene) and ##STR23##Data processing: SIC 7000B (manufactured by System Instrument Co.)

The segment (A) and segment (B) can contain one or more recurring unitsother than their predominant recurring units of the formulae

and ##STR24## to an extent that the objects of the present invention arenot impaired.

In general, these other recurring units can be introduced into thecopolymers by using the corresponding various dihalogenated aromaticcompounds as comonomers.

Physical Properties of the Copolymers

Physical properties and other characteristics of the poly(arylenethioether-ketone) copolymers according to this invention will nextdescribed in detail from the viewpoint of processability, meltstability, crystallinity and the like.

(1) Processability:

The melting point of PTK homopolymer as polymerized is about 360° C. Theextent of a reduction in the melting point due to copolymerization withanother monomer of a different kind, ΔTm=[360° C.-Tm (melting point ofcopolymer)] is generally proportional to the extent of a reduction inthe melt processing temperature.

Accordingly, ΔTm can be used as an index indicative of processingtemperature reducing effect, namely, processability improving effect.

ΔTm may preferably be 10°-80° C., more preferably 20°-70° C., mostpreferably 30°-65° C. If ΔTm is lower than 10° C., there is a potentialproblem that the processability improving effect may not be sufficient.If ΔTm is higher than 80° C. on the other hand, there is anotherpotential problem that the copolymer may lose the characteristics as aheat-resistant resin. ΔTm outside the above range is therefore notpreferred.

(2) Crystallinity:

One of great features of the copolymers according to this inventionresides in that they have not only excellent processability but alsohigh crystallinity. Crystallinity imparts high heat resistance to acopolymer. To have a copolymer equipped with high heat resistance, it isessential that the copolymer has sufficient crystallinity.

In general, melt crystallization enthalpy, ΔHmc is proportional to thedegree of crystallization when a molten polymer undergoescrystallization. On the other hand, melt crystallization temperature,Tmc serves as an index of the readiness of crystallization. Therefore,the melt crystallization enthalpy, ΔHmc (400° C.) and meltcrystallization temperature, Tmc (400° C.) of a copolymer according tothis invention as measured when cooled at a rate of 10° C./minimmediately after being heated to 400° C. in an inert gas atmosphere bymeans of a differential scanning calorimeter (hereinafter abbreviated as"DSC") can be used as indices of the crystallinity of the copolymer.

In addition, residual melt crystallization enthalpy, ΔHmc (400° C./10min) and melt crystallization temperature, Tmc (400° C./10 min)measurable upon determination of the residual crystallinity, both ofwhich will be described subsequently, can be used as an index of notonly melt stability but also crystallinity.

The copolymers according to this invention may preferably have ΔHmc(400° C.) of at least 15 J/g, more preferably at least 20 J/g, mostpreferably at least 25 J/g. On the other hand, Tmc (400° C.) maydesirably be at least 180° C., with at least 190° C. being morepreferred. Copolymers having ΔHmc (400° C.) smaller than 15 J/g or Tmc(400° C.) lower than 180° C. may have insufficient heat resistance asheat-resistant polymers and are hence not preferred.

(3) Melt stability:

The greatest feature of the copolymers according to this inventionresides in that they have melt stability sufficient to permit theapplication of conventional melt processing techniques. Polymers of poormelt stability tend to lose their crystallinity or to undergocrosslinking or carbonization, resulting in a rapid increase in meltviscosity, upon melt processing. It is hence possible to obtain an indexof the melt processability of a polymer by investigating the residualcrystallinity of the polymer after holding it at an elevated temperatureof its melt processing temperature or higher for a predetermined periodof time. The residual crystallinity can be evaluated quantitatively bymeasuring the melt crystallization enthalpy of the polymer by a DSC.

Specifically, it is possible to use as indices of the melt stability ofa copolymer its residual melt crystallization enthalpy, ΔHmc (400° C./10min) and melt crystallization temperature, Tmc (400° C./10 min), whichare determined at a cooling rate of 10° C./min after the copolymer isheld at 50° C. for 5 minutes in an inert gas atmosphere, heated to 400°C. at a rate of 75° C./min and then held for 10 minutes at 400° C. whichis higher than the melt processing temperature of the copolymer. In thecase of a copolymer having poor melt stability, it undergoescrosslinking or the like under the above conditions, namely, when it isheld for 10 minutes at the high temperature of 400° C., whereby thecopolymer loses its crystallinity substantially.

The copolymers of this invention are polymers having the physicalproperties that their residual melt crystallization enthalpies, ΔHmc(400° C./10 min) are at least 10 J/g, more preferably at least 15 J/g,most preferably at least 20 J/g and their melt crystallizationtemperatures, Tmc (400° C./10 min) are at least 170° C., more preferablyat least 180° C., most preferably at least 190° C. A polymer, whose ΔHmc(400° C./10 min) is smaller than 10 J/g or whose Tmc (400° C./10 min) islower than 170° C., tends to lose its crystallinity or to induce a meltviscosity increase upon melt processing, so that difficulties areencountered upon application of conventional melt processing techniques.

Further, the ratio of melt crystallization enthalpy to residual meltcrystallization enthalpy, namely, ΔHmc (400° C.)/ΔHmc (400° C./10 min)can also be used as an index of melt stability. Deterioration by heatbecomes smaller as this ratio decreases. Therefore, it is preferablythat ΔHmc (400° C./10 min) is at least 10 J/g and the above ratio is 5or smaller, more preferably 3 or smaller.

(4) Melt viscosity:

In this invention, the melt viscosity, η* of each copolymer is used asan index of its molecular weight. Specifically, a polymer sample isfilled in a Capirograph manufactured by Toyo Seiki Seisaku-Sho, Ltd. andequipped with a nozzle having an inner diameter of 1 mm and an L/D ratioof 10/1 and is preheated at 350° C. for 5 minutes. Its melt viscosity,η* is measured at a shear rate of 1,200/sec.

The copolymers of the present invention have a melt viscosity, η* of2-100,000 poises, preferably 5-50,000 poises, more preferably 10-30,000poises. Those having a melt viscosity, η* lower than 2 poises have anunduly low molecular weight, so that their flowability is too high toconduct conventional melt processing. Even if melt-formed or melt-moldedproducts are obtained, their physical properties are considerablyinferior. Such low melt viscosities are therefore not preferred. On theother hand, those having a melt viscosity, η* higher than 100,000 poiseshave an unduly high molecular weight, so that their flowability is toolow to conduct conventional melt processing. Such high melt viscositiesare therefore not preferred either.

PRODUCTION PROCESS OF COPOLYMERS

A variety of processes may be contemplated for the production of thecopolymers, for example, including:

(1) A dihalogenated aromatic compound consisting principally of a4,4'-dihalobenzophenone is added to and reacted with a PATE oligomerwhich has been prepared in advance, whereby a PTK segment (A) is formedto form a copolymer.

(2) A dihalogenated aromatic compound consisting principally of adihalobenzene is added to and reacted with a PTK oligomer which has beenprepared in advance, whereby a PATE segment (B) is formed to form acopolymer.

(3) A PTK oligomer and a PATE oligomer, which have been preparedseparately, are chemically combined together.

The present inventors carefully studied those processes. As a result, ithas been found that the processes (1) and (3) are preferable forobtaining the copolymers of this invention.

A. Raw materials for copolymers:

In the process for the production of a copolymer of this invention, analkali metal sulfide and a dihalogenated aromatic compound are employedas principal raw materials for the polymer, amd as reactionpolymerization media are employed an organic amide solvent and waterincluding water of hydration.

(1) Alkali metal sulfide:

Illustrative examples of the alkali metal sulfide useful in the practiceof this invention include lithium sulfide, sodium sulfide, potassiumsulfide, rubidium sulfide, cesium sulfide and mixtures thereof. Amongthese alkali metal sulfides, sodium sulfide is industrially preferredfor its low price. An alkali metal sulfide which may be formed in situin the reaction system can also be used.

(2) Dihalogenated aromatic compound:

The dihalogenated aromatic compound employed in the present inventionfor the formation of the PTK segment (A), including a PTK oligomer,consists principally of one or more dihalobenzophenones, i.e.,4,4'-dichlorobenzophenone and/or 4,4'-dibromobenzophenone.

The dihalogenated aromatic compound used in the present invention forthe formation of the PATE segment (B), including a PATE oligomer,consists principally of a dihalobenzene such as p-dichlorobenzene orm-dichlorobenzene.

As other copolymerizable dihalogenated aromatic compounds, may bementioned, for example, dihalobenzophones other than 4,4'-isomers,dihaloalkylbenzenes, dihalobiphenyls, dihalodiphenyl sulfones,dihalonaphthalenes, bis(halogenated phenyl)methanes, dihalopyridines,dihalothiophenes and dihalobenzonitriles, and mixtures thereof. Assubstituent halogen atoms, chlorine or bromine atoms may be usedpreferably from the economical viewpoint. Within a range not giving toomuch effect to cost, a small amount of a fluorine compound, for example,difluorobenzophenone or the like may also be used in combination.

It is also permissible to produce a copolymer, which has a partiallycrosslinked and/or branched structure, by causing a trihalogenated orhigher polyhalogenated compound to exist in a reaction system in such asmall amount that the processability and physical properties of thecopolymer may not be impaired to any substantial extent.

(3) Organic amide solvent:

As reaction media useful for the production process of the copolymersaccording to this invention, aprotic polar organic solvents havingexcellent heat stability and alkali resistance can be used. Of these,organic amide solvents, including carbamic amides, and sulfone solventsare particularly preferred.

As such organic amide solvents and sulfone solvents, may be mentionedN-methylpyrrolidone, N-ethylpyrrolidone, N,N'-ethylenedipyrrolidone,pyrrolidones, hexamethylphosphoric triamide, tetramethylurea,dimethylimidazolidinone, dimethylacetamide, ε-caprelactam,N-ethylcaprolactam, sulfolane, diphenyl sulfone, etc. They may also beused as a mixed solvent. Among these organic amide solvents,N-methylpyrrolidone or its mixed solvent is particularly preferred fromthe viewpoint of the readiness in obtaining a melt-stable copolymer,thermal and chemical stability, economy, etc.

B. Polymerization process and reaction conditions:

For the preparation of the PATE oligomer, for the reaction in which thePTK segment is formed in the presence of the PATE oligomer to form acopolymer, for the preparation of the PTK oligomer and for the reactionin which the PTK oligomer and PATE oligomer are combined together toform a copolymer, it is necessary to conduct the reaction under specialconditions, namely by causing water to exist in specific amounts in thereaction systems, controlling the monomer compositions suitably,regulating the polymerization temperatures appropriately, and limitingreaction time at high temperatures to specific short periods of time. Itis effective for the production of copolymers having more preferablephysical properties, for example, to choose a suitable material for thereactor and to apply stabilization treatment in a final stage of thereaction. Unless these reaction conditions are suitably controlled, itis difficult to provide crystalline copolymers having melt stabilitysuitable for conventional melt processing.

Preparation Process of Oligomers

(1) PATE oligomer:

The PATE oligomer employed as a raw material for the copolymer of thisinvention can be prepared by having an alkali metal sulfide and adihalogenated aromatic compound, which consists principally of adihalobenzene, undergo a reaction in the presence of water in an organicamide solvent under the following conditions (a)-(c):

(a) The ratio of the water content to the amount of the charged organicamide solvent is within a range of 0.1-15 (mol/kg), preferably 0.3-12(mol/kg), more preferably 0.5-11 (mol/kg).

(b) The ratio of the amount of the charged dihalogenated aromaticcompound to the amount of the charged alkali metal sulfide is within arange of 0.3-0.9 (mol/mol), preferably 0.4-0.8 (mol/mol), morepreferably 0.5-0.75 (mol/mol).

(c) The reaction is conducted at a temperature within a range of150°-290° C., preferably 200°-280° C., and controlled in such a mannerthat the number-average polymerization degree of the resulting oligomeris higher than 1 but lower than 10, preferably within a range of 2-9,more preferably within a range of 3-8.

In this reaction, the amount of the charged alkali metal sulfide is morethan that of the charged dihalogenated aromatic compound. Therefore, thePATE oligomer formed has at least one terminal thiolate group. Theoligomer having at least one terminal thiolate group means an oligomerhaving a thiolate group on its each terminal or one terminal, or amixture thereof. The PATE oligomer may contain some crosslinkedstructure and/or branched structure introduced typically by allowing atrihalobenzene or higher polyhalobenzene to present in a small amount inthe polymerization reaction system. Incidentally, among the recurringunits of the formula ##STR25## the recurring unit of the formula##STR26## is preferred.

(2) PTK oligomer:

The PTK oligomer employed as a raw material for the copolymer of thisinvention can be prepared in the following manner.

Namely, the PTK oligomer can be prepared by having an alkali metalsulfide and a dihalogenated aromatic compound, which consistsprincipally of 4,4'-dichlorobenzophenone and/or4,4'-dibromobenzophenone, undergo a reaction in the presence of water inan organic amide solvent under the following conditions (a)-(b):

(a) The ratio of the water content to the amount of the charged organicamide solvent is within a range of 0.1-15 (mol/kg), preferably 1-12(mol/kg), more preferably 2.5-10 (mol/kg). Water contents lower than 0.1mole can hardly provide a PTK oligomer having high melt stability andmoreover tend to induce decomposition in the polymerization reaction. Onthe other hand, water contents higher than 15 moles result in areduction in the reaction rates. Neither such high nor low watercontents are hence preferred economically.

(b) The reaction is conducted at a temperature within a range of60°-300° C. with the proviso that the reaction time at 210° C. andhigher is not longer than 10 hours. The temperature may preferably bewithin a range of 150°-290° C., more preferably 170°-260° C.

The PTK oligomer has at least one terminal halogen atom. The PTKoligomer may contain some crosslinked structure and/or branchedstructure introduced typically by allowing a trihalobenzophenone orhigher polyhalobenzophenone to present in a small amount in thepolymerization reaction system.

The reduced viscosity of the PTK oligomer is 0.2 dl/g or lower,preferably 0.1 dl/g or lower, more preferably 0.05 dl/g or lower asdetermined by viscosity measurement at 30° C. and a polymerconcentration of 1.0 g/dl in 98% concentrated sulfuric acid.

The ratio of the amount of the charged dihalogenated aromatic compoundto the amount of the charged alkali metal sulfide upon synthesis of thePTK oligomer may preferably be at least 1.15 (mol/mol), more preferablyat least 1.2 (mol/mol), most preferably at least 1.3 (mol/mol). Besides,with respect to the ratio of the amount of the charged organic amidesolvent to the amount of the charged alkali metal sulfide in thecomposition of charges upon synthesis of the PTK oligomer, it isdesirable to charge the organic amide solvent, in general, in an amountof 0.6-100 kg, more preferably 0.7-50 kg per mole of the amount of thecharged alkali metal sulfide, depending upon the composition of thecharged dihalogenated aromatic compound.

Production Process of Copolymers

As a first production process for each copolymer according to thisinvention, may be described the process (Production Process No. 1) inwhich a PATE oligomer is prepared in advance and at least one PTKsegment is formed in the presence of the PATE oligomer. This process issubstantially a two-step process.

In the second step, the reaction mixture containing the oligomerobtained in the first step may be mixed with a dihalogenated aromaticcompound consisting principally of at least one dihalobenzophenoneselected from 4,4'-dichlorobenzophenone and 4,4'-dibromobenzophenone,and the resultant mixture may be heated without further addition of anyalkali metal sulfide, organic amide solvent or water, thereby obtaininga copolymer. It goes without saying that the alkali metal sulfide,organic amide solvent or water may be added further in the second step.

As a second production process for each copolymer according to thisinvention, may be described the process (Production Process No. 2) inwhich PATE and PTK oligomers are prepared in advance and are thenreacted to combine them together. This process is substantially athree-step process.

The reaction conditions employed in the synthesis stage of the copolymerwill hereinafter be described in further detail.

(1) Water content:

In the process for the preparation of the copolymer of this invention,the water content in the reaction system may desirably be within a rangeof 0.1-15 moles, preferably 2.5-15 moles, more preferably 3.5-14 molesper kg of the amount of the charged organic amide solvent. Watercontents lower than 0.1 mole can hardly provide a copolymer having highmelt stability and moreover tend to induce decomposition in thepolymerization reaction. On the other hand, water contents higher than15 moles result in a reduction in the reaction rates, so that thereaction requires an unduly long period of time. Such high watercontents are hence not preferred in industry. In order to adjust thewater content in a reaction system, the water content may be reduced bydistillation or the like or may be increased by adding water prior tothe initiation of a polymerization reaction.

(2) Composition of monomers charged:

The ratio of the total amount of the dihalogenated aromatic compound tothe total amount of the alkali metal sulfide, both charged uponsynthesis of the copolymer, may desirably be in a range of 0.95-1.2(mol/mol), more preferably 0.97-1.10 (mol/mol), most preferably0.98-1.05 (mol/mol). Here, the term "the total amount of the chargedalkali metal sulfide" means the sum of the amount of the alkali metalsulfide charged upon synthesis of the PTK oligomer and/or the PATEoligomer and the amount of the alkali metal sulfide charged uponsynthesis of the copolymer. When a copolymer is synthesized using aportion or portions of synthesized PTK oligomer and/or PATE oligomer,the amounts of the alkali metal sulfide and dihalogenated aromaticcompound charged upon synthesis of each oligomer must be taken intoconsideration.

Ratios smaller than 0.95 can hardly provide a copolymer having excellentmelt stability and tend to induce decomposition during the reaction. Onthe other hand, ratios greater than 1.2 can only provide a copolymerhaving a low molecular weight. Besides, with respect to the ratio of theamount of the charged organic amide solvent to the amount of the chargedalkali metal sulfide in the compositions of charges upon synthesis ofthe PATE oligomer and copolymer, it is desirable to charge the organicamide solvent, in general, in an amount of 0.3-5 kg, more preferably0.4-3 kg per mole of the amount of the charged alkali metal sulfide,depending upon the composition of the charged dihalogenated aromaticcompound.

Where the alkali metal sulfide is lost by a distilling operation or thelike prior to the initiation of the reaction, the term "the amount ofthe charged alkali metal sulfide" as used herein means the remainingamount which is obtained by subtracting the loss from the amountactually charged.

The segment (A) serves to impart high degree of heat resistance andcrystallinity to the copolymer. On the other hand, the segment (B)contributes to the reduction of the processing temperature and thegranulation while maintaining the high crystallinity. Accordingly, theratio of the charged amount of the dihalogenated aromatic compoundconsisting principally of the dihalobenzene in the first step to thecharged amount of the dihalogenated aromatic compound consistingprincipally of the dihalobenzophenone in the second step is controlledwithin a range of 0.1-10 (mol/mol), preferably 0.2-7.5 (mol/mol), morepreferably 0.3-6.0 (mol/mol). Further, copolymers in each of which thisratio is within a range of 0.1-1.9, preferably 0.2-1.9 featureparticularly good heat resistance and high crystallinity. Ratios in arange of 2-10, preferably 2-7.5 give copolymers excellent especially inprocessability while retaining excellent crystallinity. However, anyratios lower than 0.1 are too low to achieve any sufficient reduction inprocessing temperature or the formation into granules. To the contrary,any ratios higher than 10 lead to a substantial reduction in heatresistance and disturb the balancing between heat resistance andprocessability. Ratios outside the above range are therefore notpreferred.

The term "the amount of the charged dihalogenated aromatic compound" asused herein should be interpreted not to include the amount of thehalogen-substituted aromatic compound added in the final stage of thereaction for effecting a stabilizing treatment to be describedsubsequently.

(3) Reaction temperature and reaction time:

In the process of this invention for the production of the copolymer,the reaction is conducted at a temperature in a range of 150°-300° C.,preferably 200°-290° C., more preferably 210°-280° C. Reactiontemperatures lower than 150° C. require an unduly long time to obtainthe copolymer and are therefore economically disadvantageous. On theother hand, reaction temperatures higher than 300° C. can hardly obtainthe copolymer in a form excellent in melt stability and moreover involvea potential problem of decomposition during the reaction.

The polymerization time required for obtaining a PTK oligomer orcopolymer of a desired molecular weight becomes shorter as thepolymerization temperature increases but becomes longer as thepolymerization temperature decreases. Accordingly, it is generallyadvantageous to conduct the polymerization at a temperature of 210° C.or higher from the viewpoint of productivity. It is however notpreferred to Conduct the reaction at a temperature of 210° C. or higherfor 10 hours or longer, because a PTK oligomer or copolymer havingexcellent melt stability can hardly be obtained under such conditions.

(4) Reactor:

In the process of this invention for the production of each of the PTKoligomer, PATE oligomer and copolymer, it is preferable to use, as areactor (including equipment employed for provisional procedures of thepolymerization reaction, for example, those required for dehydration andthe like), a reactor which is made of a corrosion-resistant material atleast at portions with which the reaction mixture is brought into directcontact. The corrosion-resistant material is supposed to be inert sothat it does not react with the reaction mixture. Preferable examples ofthe corrosion-resistant material include titanium materials such astitanium and titanium-containing alloys and nickel-containingcorrosion-resistant materials. Of these, it is particularly preferred touse a reactor lined with a titanium material.

The use of a reactor made of a corrosion-resistant material such as thatdescribed above makes it possible to obtain a copolymer having high heatresistance and molecular weight.

(5) Treatment in the final stage of the reaction:

Although a copolymer having excellent melt stability can be obtained bythe above-described production process, the copolymer can be obtained ina form improved further in melt stability by adding a certain kind ofhalogen-containing compound to the reaction system and causing it toundergo a reaction in a final stage of the reaction.

As halogen-containing compounds, may be mentioned C₁ -C₃ alkyl halidesand halogen-substituted aromatic compounds. It is particularlypreferable to use at least one halogen-substituted aromatic compoundwhich contains at least one group having electron-withdrawing propertyat least equal to --CO-- group. As illustrative examples of such ahalogen-substituted aromatic compound, may be mentionedbis(chlorobenzoyl)benzenes, dihalobenzophenones, dihalodiphenylsulfones,monohalobenzophenones and the like, and mixtures thereof.

It is desirable to conduct the final-stage treatment by adding theabove-mentioned halogen-substituted aromatic compound in an amount of0.1-20 moles, preferably 0.5-10 moles per 100 moles of the chargedalkali metal sulfide to the polymerization reaction system in the finalstage of the reaction and then allowing it to react at 60°-300° C., morepreferably 150°-290° C., most preferably 220°-280° C. for 0.1-20 hours,more preferably 0.1-8 hours.

(6) Conditions for the granulation:

Another principal feature of the process of this invention for theproduction of the copolymer resides in that the copolymer excellent inmelt stability can be obtained as granules by suitably choosing theaforementioned reaction conditions for the copolymer further. Reactionconditions for obtaining at least 50 wt. % of the resulting copolymer asgranules collectible by means of a sieve having an opening size of 75 μm(200 mesh) will next be described in further detail.

(i) Weight ratio of the total amount of segment or segments (B) to thetotal amount of segment or segments (A) in the copolymer:

The weight proportion of segment or segments (B) in the copolymer is animportant parameter since each segment (B) contributes to thegranulation. When it is desired to obtain the copolymer of thisinvention as granules, it is necessary to control the ratio of the totalamount of segment or segments (B) to the total amount of segment orsegments (A) at 0.2-5, preferably 0.3-4, more preferably 0.4-3, all byweight.

If this ratio is lower than 0.2, it becomes difficult to obtain thecopolymer as granules. On the contrary, ratios higher than 5 lead to asubstantial reduction in the heat resistance of the copolymer. Neithersuch low nor high ratios are preferred.

(ii) Reaction temperature and time for the granulation:

To obtain the copolymer as granules, it is desirable to raise thereaction temperature to a high temperature of at least 240°-290° C.,more preferably 250°-290° C. in the course of the reaction or in a finalstage of the reaction. Reaction temperatures lower than 240° C. make itdifficult to obtain the copolymer as granules. On the contrary, it isdifficult to obtain the copolymer in a form excellent in melt stabilityif the reaction temperature is higher than 290° C.

The time required for obtaining the copolymer as desired granulesbecomes shorter as the reaction temperature increases. Conversely, itbecomes longer as the reaction temperature decreases. Therefore, it isgenerally advantageous from the viewpoint of productivity to conduct thereaction at a high temperature of 250° C. or higher. It however becomesdifficult to obtain the copolymer in a form excellent in melt stabilityif the reaction at high temperatures of 250° C. and higher is continuedfor 7 hours or longer.

C. Collection of copolymers:

To collect the copolymer from the reaction mixture, the following methodcan be followed. Namely, after completion of the reaction including thetreatment in the final stage if applied, the reaction mixture issubjected to flushing and/or distillation, whereby the solvent isremoved either partly or wholly to concentrate the reaction mixture. Ifnecessary, the concentrate may be heated to remove any remainingsolvent. The resulting solids or concentrate is washed with water and/oran organic solvent to eliminate soluble components such as salts formedin the reaction. The residue is again dried under heat to collect thepolymer.

By suitably choosing the reaction conditions in the process of thisinvention for the production of the copolymer, at least 50 wt. % of theresulting copolymer can be obtained as granules which can be captured ona screen having an opening size of 75 μm (200 mesh), more preferably 106μm (140 mesh), most preferably 150 μm (100 mesh).

As has been described above, the copolymer can be easily collected asgranules by a screen or the like from the reaction mixture aftercompletion of the reaction. The granular polymer thus collected iswashed with water and/or an organic solvent and then dried under heat toobtain it in a dry form. Since the copolymer is in a granular form andhas excellent handling property, it permits easy separation, waterwashing, transportation, metering and the like.

APPLICATION FIELDS

The copolymers according to the present invention are crystalline andpermit the application of conventional melt processing techniques. Theycan be formed or molded into various heat-resistant products and canthen be used in various fields. For example, extrusion products mayinclude sheets, plates, pipes, tubes, covered conductors, etc.Injection-molded products may be used as electronic and electric parts,car parts, etc. On the other hand, unstretched films may be employed asbase films for magnetic recording, capacitor films, printed circuitboards, insulating films, prepreg sheets, and so on.

ADVANTAGES OF THE INVENTION

The present invention can provide crystalline poly(arylenethioether-ketone) copolymers uniform in composition and excellent inheat resistance, melt stability, processability and handling properties.

The invention can also economically provide such poly(arylenethioether-ketone) copolymers. The invention can also provide variousformed or molded products of such poly(arylene thioether-ketone)copolymers.

EMBODIMENTS OF THE INVENTION

The present invention will hereinafter be described in further detail bythe following examples and comparative examples. It should however beborne in mind that the present invention is not limited only to thefollowing examples.

EXAMPLE 1 Production Process No. 1 Synthesis of PATE Oligomer

A titanium-lined reactor was charged with 3200 g of hydrated sodiumsulfide (water content: 53.8 wt. %) and 6000 g of N-methylpyrrolidone(hereinafter abbreviated as "NMP"). While gradually heating the contentsto 203° C. in a nitrogen gas atmosphere, 2376 g of an NMP solution,which contained 1309 g of water, and 12.98 g of hydrogen sulfide weredistilled out. Thereafter, 103 g of water was added. A liquid mixtureconsisting of 1910 g of p-dichlorobenzene (hereinafter abbreviated as"PDCB") and 4350 g of NMP was then fed, followed by polymerization at220° C. for 4 hours and further at 230° C. for 4 hours (PDCB/sodiumsulfide=0.70 mol/mol; water content/NMP=3.1 mol/kg), whereby about13.174 kg of a reaction slurry (Slurry S₁) containing a poly(p-phenylenethioether) (hereinafter abbreviated as "PPTE") oligomer (Oligomer P₁)was obtained.

A portion of Reaction Slurry S₁ was sampled out, and the amount of theremaining monomer and the number-average polymerization degree weredetermined. The amount of PDCB (remaining monomer) in the reactionslurry as determined by gas chromatography was lower than 0.1 wt. % ofthe charged amount. The number-average polymerization degree of OligomerP₁ was 5.

The number-average polymerization degree was determined by preparing asample in the following manner and subjecting it to high-temperatureGPC. Immediately after completion of the polymerization of the oligomer,a portion of the reaction slurry was sampled out and then poured intowater, and the water was adjusted to a pH of 3.0 with hydrochloric acidto have the oligomer precipitated. The oligomer was collected byfiltration, thoroughly washed in distilled water and then dried at roomtemperature under reduced pressure in a vacuum drier, thereby obtainingan oligomer sample. The thus-obtained oligomer sample was added toα-chloronaphthalene to a concentration of 0.05 wt. % and dissolvedthereinunder heat, thereby preparing a sample solution for GPC. Themeasuring conditions for high-temperature GPC are as described above.

Synthesis of Copolymer

A titanium-lined reactor was charged with 8.0 g of hydrated sodiumsulfide (water content: 53.8 wt. %), 63.4 g of 4,4'-dichlorobenzophenone(hereinafter abbreviated as "DCBP"), 501 g of Reaction Slurry S₁ thusobtained, 278 g of NMP and 89.7 g of water. After the reactor beingpurged with nitrogen, the contents were heated to 265° C. at which theywere polymerized for 0.5 hour. To conduct the stabilizing treatment inthe final stage of polymerization, the reaction mixture was cooled to240° C., in which a mixture of 7.5 g of DCBP and 70 g of NMP was putunder pressure to react them at 240° C. for 0.5 hour.

The reaction conditions upon synthesis of the copolymer were as follows:

(1) The molar ratio of the total amount of the charged dihalogenatedaromatic compound (the sum of the amount of PDCB charged upon synthesisof Oligomer P₁ and the amount of DCBP charged upon synthesis of thecopolymer) to the total amount of the charged alkali metal sulfide (thesum of the amount of effective sodium sulfide charged upon synthesis ofOligomer P₁ and the amount of sodium sulfide charged upon synthesis ofthe copolymer) was 0.99.

(2) The molar ratio of the amount of PDCB charged in the first step tothe amount of DCBP charged in the second step was 2.

(3) The ratio of the water content to the organic amide (NMP) was about10 mol/kg.

Collection of Copolymer

The resulting reaction mixture in the form of a slurry was diluted witha substantially equiamount of NMP and the granular polymer thus obtainedwas collected by a screen having an opening size of 150 μm (100 mesh).The polymer was washed three times with NMP and further three times withwater, and then dried at 100° C. for 24 hours under reduced pressure toobtain a copolymer (Copolymer C₁). The collection rate of Copolymer C₁was 88%.

Inherent Properties of Copolymer C₁

Copolymer C₁ was in the form of granules having an average particle sizeof about 600 μm. By an infrared (IR) spectrum analysis, a strongabsorption peak attributed to ketone group was observed at 1640 cm⁻¹.Wide angle X-ray diffraction which was conducted using "RAD-B System"manufactured by Rigaku Denki Kabushiki Kaisha showed a diffractionpattern apparently different from that corresponding to PATEhomopolymer, PTK homopolymer or a blend thereof, or a block copolymer ofPATE and PTK. The content of sulfur in Copolymer C₁ was determined bymeans of a sulfur analyzer ("EMIA-510" manufactured by Horiba Ltd.).

The weight fraction W_(b) (wt. %) of the recurring units ##STR27## inthe copolymer can be calculated in accordance with the followingequation and was 51%.

    W.sub.b =(W-W.sub.1)/(W.sub.2 -W.sub.1)×100

wherein W means the weight fraction of sulfur in the copolymer, W₁denotes the weight fraction of sulfur in PTK recurring unit, and W₂represents the weight fraction of sulfur in PATE recurring unit.

Physical Properties of Copolymer

The melt viscosity of Copolymer C₁ was 350 poises. Tmc and ΔHmc areshown in Table 1. Incidentally, the copolymer as polymerized had amelting point (Tm) of 312° C.

EXAMPLE 2 Production Process No. 1 Synthesis of PATE Oligomer

A titanium-lined reactor was charged with 1000.6 g of hydrated sodiumsulfide (water content: 53.7 wt. %), 6000 g of NMP and 443.2 g of PDCB.The contents were polymerized at 220° C. for 10 hours (PDCB/sodiumsulfide=0.508 mol/mol; water content/NMP=4.98 mol/kg), thereby obtaininga reaction slurry (Slurry S₂).

The amount of PDCB (remaining monomer) in the reaction slurry asdetermined in the same manner as in Example 1 was 0.1 wt. % of thecharged amount. The number-average polymerization degree of theresultant oligomer (Oligomer P₂) was 5.

Synthesis of Copolymer

A titanium-lined 1-l reactor was charged with 682.9 g of thethus-obtained Reaction Slurry S₂ and 69.3 g of DCBP. After the reactorbeing purged with nitrogen, the contents were heated to 240° C. at whichthey were polymerized for 3 hours.

The reaction conditions upon synthesis of the copolymer were as follows:

(1) The molar ratio of the total amount of the charged dihalogenatedaromatic compound (the sum of the amount of PDCB charged upon synthesisof Oligomer P₂ and the amount of DCBP charged upon synthesis of thecopolymer) to the total amount of the charged alkali metal sulfide (theamount of effective sodium sulfide charged upon synthesis of OligomerP₂) was 1.01.

(2) The molar ratio of the amount of PDCB charged in the first step tothe amount of DCBP charged in the second step was 1.

(3) The ratio of the water content to the organic amide (NMP) was about5 mol/kg.

Collection of Copolymer

The resulting reaction mixture in the form of a slurry was filtered by afilter paper (class: 5A) to collect solids. The thus-collected solidswere washed with acetone and water repeatedly and then dried at 100° C.,thereby obtaining a copolymer (Copolymer C₂). The collection rate ofCopolymer C₂ was 96%.

Physical Properties of Copolymer

The physical properties of Copolymer C₂ are shown in Table 1. The meltviscosity of Copolymer C₂ was 60 poises. Copolymer C₂ was soluble inconcentrated sulfuric acid, and its reduced viscosity was 0.28 dl/g asmeasured at 30° C. and a polymer concentration of 0.4 g/dl.

EXAMPLE 3 Production Process No. 2 Synthesis of PATE Oligomer

A titanium-lined reactor was charged with 3.20 kg of hydrated sodiumsulfide (water content: 53.8 wt. %) and 6.00 kg of NMP. While graduallyheating the contents to 203° C. in a nitrogen gas atmosphere, 2.326 kgof an NMP solution, which contained 1.282 kg of water, and 10.27 g ofhydrogen sulfide were distilled out. Thereafter, 0.076 kg of water wasadded. A liquid mixture consisting of 2.193 kg of p-dichlorobenzene and4.370 kg of NMP was then fed, followed by polymerization at 220° C. for4 hours and further at 230° C. for 4 hours (PDCB/sodium sulfide=0.80mol/mol; water content/NMP=3.1 mol/kg), whereby about 13.503 kg of areaction slurry (Slurry S₃) containing an oligomer (Oligomer P₃) of PPTEwas obtained. A portion of the reaction slurry was sampled out, and theamount of the remaining monomer and the number-average polymerizationdegree were determined in the same manner as in Example 1. As a result,the amount of the remaining monomer was lower than 0.1 wt. % of thecharged amount, and the number-average polymerization degree of OligomerP₃ was 8.

Synthesis of PTK Oligomer

A titanium-lined reactor was charged with 2.271 moles of DCBP, 206.8 gof hydrated sodium sulfide (water content: 53.8 wt. %), 114 g of waterand 2498 g of NMP. After the reactor being purged with nitrogen, thecontents were maintained at 220° C. for 1 hour (water content/NMP=about5 mol/kg) to obtain a reaction slurry (Slurry KS₁) containing a PTKoligomer (Oligomer K₁). After completion of the polymerization of theoligomer, a portion of the reaction slurry was sampled out and thenpoured into water, and the water was adjusted to a pH of 3.0 withhydrochloric acid to have the oligomer precipitated. The oligomer wascollected by filtration, thoroughly washed in distilled water and thendried at room temperature under reduced pressure in a vacuum drier,thereby obtaining an oligomer sample. The thus-obtained oligomer samplewas dissolved in 98% concentrated sulfuric acid to give a concentrationof 1.0 g/dl so as to measure the reduced viscosity of the oligomer at30° C. The reduced viscosity was extremely low and the value was lowerthan 0.05 dl/g.

Synthesis of Copolymer

A titanium-lined reactor was charged with 448 g of Reaction Slurry S₃containing PATE Oligomer P₃, 377 g of Reaction Slurry KS₁ containing PTKOligomer K₁ and 64 g of water. After the reactor being purged withnitrogen, the contents were maintained at 265° C. for 0.5 hour to reactthem. To conduct the stabilizing treatment in the final stage ofpolymerization, the reaction mixture was cooled to 240° C., in which amixture of 7.5 g of DCBP and 70 g of NMP was put under pressure to reactthem at 240° C. for 0.5 hour.

The reaction conditions upon synthesis of the copolymer were as follows:

(1) The molar ratio of the total amount of the charged dihalogenatedaromatic compound (the sum of the amount of PDCB charged upon synthesisof PATE Oligomer P₃ and the amount of DCBP charged upon synthesis of PTKOligomer K₁) to the total amount of the charged alkali metal sulfide(the sum of the amount of sodium sulfide charged upon synthesis of PATEOligomer P₃ and the amount of sodium sulfide charged upon synthesis ofPTK Oligomer K₁) was 0.98.

(2) The molar ratio of the amount of PDCB charged in the first step tothe amount of DCBP charged in the second step was 2.

(3) The ratio of the water content to the organic amide (NMP) was about10 mol/kg.

Collection of Copolymer

The resulting reaction mixture in the form of a slurry was diluted witha substantially equiamount of NMP and the granular polymer thus obtainedwas collected by a screen having an opening size of 150 μm (100 mesh).The polymer was washed three times with NMP and further three times withwater, and then dried at 100° C. for 24 hours to obtain a copolymer(Copolymer C₃) in the form of granules having an average particle sizeof 1200 μm. The collection rate was 80%.

Physical Properties of Copolymer

The melt viscosity of Copolymer C₃ was 610 poises. Physical propertiessuch as Tmc and ΔHmc are shown collectively in Table 1. Incidentally, Tmof the copolymer as polymerized was 316° C.

COMPARATIVE EXAMPLE 1 Synthesis of PTK Homopolymer

A titanium-lined reactor was charged with 9.0 moles of DCBP, 9.0 molesof hydrated sodium sulfide (water content: 53.6 wt. %) and 9.0 kg ofNMP. After the reactor being purged with nitrogen, the resultant mixturewas maintained at 240° C. for 2 hours and at 260° C. for 30 minutes toreact them (water content/NMP=5.0 mol/kg). The reactor was cooled, andthe reaction mixture in the form of a slurry was taken out of thereactor. A portion of the slurry was passed through a screen having anopening size of 75 μm (200 mesh). However, no granular polymer wascollected at all. The remaining slurry was poured into about 20 litersof acetone to have the resultant polymer precipitated. The polymer wascollected by filtration, and then washed twice with acetone andadditionally twice with water. Acetone and water were removed to obtainthe polymer in a wet form. The wet polymer was dried at 80° C. for 24hours, thereby obtaining a polymer (Polymer R₁) as an ivory powder.

The particle size of Polymer R₁ thus obtained was measured by an imageanalyzer ("OMNICON" trade mark; manufactured by Shimadzu Corp.). Theaverage particle size was 10.6 μm. Particles not greater than 6 μmamounted to 60.5 wt. %. On the other hand, particles of 30 μm andgreater accounted for 0.4 wt. % only. The bulk density of Polymer R₁ was0.24 g/dl. Incidentally, Tm of the polymer as polymerized was 362° C.Polymer R₁ thus obtained was soluble in 98% concentrated sulfuric acidbut was insoluble in α-chloronaphthalene even at 225° C.

COMPARATIVE EXAMPLE 2 Experimental Granulation by Co- and Re-Dissolutionof Homopolymers

A titanium-lined 1-l reactor was charged with 35 g of fine particulatePTK Polymer R₁ obtained in Comparative Example 1 and 65 g ofpoly(p-phenylene thioether) ("FORTRON #W214", trade mark, product ofKureha Chemical Industry Co., Ltd.) and further with 500 g of NMP and 45g of water. The contents were maintained at 260° C. for 2 hours. Aftercooling, the resultant slurry was passed through a screen having anopening size of 75 μm (200 mesh) to collect a particulate polymer. Fromthe filtrate, a fine powdery polymer was also collected using a filterpaper (class: 5A). The polymers thus collected were separately washedand dried in a similar manner to Example 1, thereby obtaining 51 g ofgranular Polymer R₂ and 37 g of fine powdery polymer.

As with poly(p-phenylene thioether), granular Polymer R₂ was insolublein 98% concentrated sulfuric acid but soluble at 225° C. inα-chloronaphthalene. Its transition temperature was substantially thesame as that of poly(p-phenylene thioether). This indicates that whenPTK and PATE are only heated together in a water-containing organicsolvent, no reaction takes place between both homopolymers and hence,any copolymers can not be obtained.

COMPARATIVE EXAMPLE 3 Synthesis of Random Copolymer

A titanium-lined 1-l reactor was charged with 0.4 mole of DCBP, 0.5 moleof hydrated sodium sulfide (water content: 54.0 wt. %), 0.1 mole of PDCBand 500 g of NMP. They were reacted at 260° C. for 2 hours [watercontent/NMP=5.0 mol/kg, DCBP/PDCB=87/13 (weight ratio)]. The reactionmixture in the form of slurry, said mixture containing Random CopolymerR₃, had a dark brown color and gave off an odor of decomposed polymers.As a result of a gas chromatographic analysis, the remaining monomer wasfounded to be PDCB. Its amount was equal to 33% of the amount charged.The slurry as the reaction mixture was passed through a screen having anopening size of 75 μm (200 mesh). It was however unable to collect anygranular polymer.

This result indicates that DCBP and PDCB are substantially differentfrom each other in reactivity and chemical stability in thepolymerization system and hence extremely poor in copolymerizabilitywith each other, so that any satisfactory copolymers can not be obtainedtherefrom.

COMPARATIVE EXAMPLE 4 Synthesis of Random Copolymer

Polymerization was conducted in a similar manner to Comparative Example3 except that 0.1 mole of DCBP and 0.4 mole of PDCB were charged in lieuof 0.4 mole of DCBP and 0.1 mole of PDCB [water content/NMP=5.0 mol/kg,DCBP/PDCB=30/70 (weight ratio)]. The reaction mixture in the form ofslurry had a dark red color and gave off an offensive odor. The slurrywas passed through a screen having an opening size of 75 μm (200 mesh).It was however unable to collect any granular polymer. A fine powderypolymer was recovered from the slurry by using a filter paper (class:5A) and was then washed and dried in a similar manner to Example 1. Tmof the resulting Random Copolymer R₄ was 240° C., which was much lowerthan the melting points of poly(p-phenylene thioether) and PTKhomopolymer.

As with Comparative Example 3, this indicates that DCBP and PDCB aresubstantially different from each other in reactivity and chemicalstability in the polymerization system and hence extremely poor incopolymerizability with each other, so that any satisfactory copolymerscan not be obtained therefrom.

COMPARATIVE EXAMPLE 5 Experimental Formation of Granules byRe-Dissolution of PTK

A titanium-lined 1-l reactor was charged with 106 g of the fine powderyPTK polymer obtained in Comparative Example 1 and also with 500 g of NMPand 45 g of water. The contents were maintained at 260° C. for 2 hours.After cooling, the resultant slurry was passed through a screen havingan opening size of 75 μm (200 mesh). It was however unable to collectany granular polymer.

COMPARATIVE EXAMPLE 6 Synthesis of PTK Homopolymer

A titanium-lined 1-l reactor was charged with 0.5 mole of DCBP, 0.5 moleof hydrated sodium sulfide (water content: 54.0 wt. %) and 500 g of NMP.After the reactor being purged with nitrogen, the resultant mixture wasmaintained at 260° C. for 2 hours to react them. The reactor was cooled,and the reaction mixture in the form of a slurry was passed through ascreen having an opening size of 75 μm (200 mesh). It was however unableto collect any granular polymers.

COMPARATIVE EXAMPLE 7 Synthesis of Block Copolymer Synthesis of PATEPrepolymer

A titanium-lined reactor was charged with 3.2 kg of hydrated sodiumsulfide (water content: 53.7 wt. %) and 6.0 kg of NMP. While graduallyheating the contents to 200° C. in a nitrogen gas atmosphere, 2.5 kg ofan NMP solution, which contained 1.33 kg of water, and 0.40 μmole ofhydrogen sulfide were distilled out. Thereafter, 0.12 kg of water wasadded. A liquid mixture consisting of 2.35 kg PDCB and 4.5 kg of NMP wasthen fed, followed by polymerization at 220° C. for 8 hours (PDCB/sodiumsulfide=0.86 mol/mol; water content/NMP=about 3 mol/kg), whereby areaction slurry containing a PATE prepolymer was obtained. Thenumber-average molecular weight of the prepolymer was 1300 (averagepolymerization degree: 12).

Synthesis of PTK Prepolymer

A titanium-lined 20-l reactor was charged with 3.640 moles of DCBP,2.039 moles of hydrated sodium sulfide (water content: 53.7 wt. %), 176g of water and 4.004 kg of NMP. After the reactor being purged withnitrogen, the contents were maintained at 220° C. for 1 hour to reactthem (water content/NMP=about 5 mol/kg), thereby obtaining a reactionslurry containing a PTK prepolymer.

Synthesis of Block Copolymer

A charge pot equipped with a heater was mounted on the titanium-lined20-l reactor with the reaction slurry containing the PTK prepolymer(temperature of slurry: 220° C.). The pot was charged with 9.12 kg ofthe reaction slurry containing the PATE prepolymer. The PATEprepolymer-containing reaction slurry was heated to 220° C. and thenadded to the PTK prepolymer-containing reaction slurry. Further, 1.146kg of water was added, and the contents were then mixed. The contentswere maintained at 260° C. for 2 hours to react them. After the contentsbeing allowed to cool down to 240° C., a final treatment of the reactionwas conducted. The final stabilizing treatment of the reaction waseffected by adding 0.4356 mole of DCBP and 0.5 kg of NMP and thenreacting the contents at 240° C. for 0.2 hour.

Collection of Block Copolymer

Collection was conducted in a similar manner to Example 1, therebyobtaining Block Copolymer B₁. The collection rate was 78%.

Physical Properties of Block Copolymer

The physical properties of Block Copolymer B₁ are shown in Table 1.

With respect to Block Copolymer B₁, a plurality of peaks correspondingto its melting points appear, and the peak width at half height isgreat. Regarding the copolymers according to this invention on the otherhand, the peak corresponding to the melting point is single and sharp.This indicates that their uniformity in composition is excellent.Incidentally, the melt viscosity of Block Copolymer B₁ was 650 poises.

                                      TABLE 1                                     __________________________________________________________________________                                       Crystallinity ·                           PATE recurring units/      melt stability                             Poly-   PTK recurring units                                                                            Transition                                                                              (400° C.)                           mer     Charged value                                                                         Analyzed value                                                                         temp. (°C.)                                                                      Tmc                                                                              ΔHmc                                  code                                                                              (weight ratio)                                                                        (weight ratio)                                                                         Tg*.sup.1                                                                          Tm*.sup.1                                                                          (°C.)                                                                     (J/g)                                   __________________________________________________________________________    Ex. 1                                                                             C.sub.1                                                                           1.0 (50/50)                                                                           1.0 (51/49)                                                                            109  300  267                                                                              51                                      Ex. 2                                                                             C.sub.2                                                                           0.5 (34/66)                                                                           0.5 (34/66)                                                                            114  324  282                                                                              47                                      Ex. 3                                                                             C.sub.3                                                                           1.0 (50/50)                                                                           1.0 (50/50)                                                                            114  306  262                                                                              50                                      Comp.                                                                             R.sub.1                                                                             0 (0/100)                                                                           Homopolymer                                                                            135  351  320                                                                              60                                      Ex. 1                                                                         Comp.                                                                             R.sub.2                                                                           1.9 (65/35)                                                                           Blend     86  285  -- --                                      Ex. 2                    (PATE)                                                                             (PATE)                                          Comp.                                                                             R.sub.3                                                                           0.1 (11/89)                                                                           Trial for                                                                              --   --   -- --                                      Ex. 3           random                                                                        copolymer                                                                     (uncollectable)                                               Comp.                                                                             R.sub.4                                                                           2.0 (67/33)                                                                           Trial for                                                                              --   295  -- --                                      Ex. 4           random                                                                        copolymer                                                     Comp.                                                                             R.sub.5                                                                             0 (0/100)                                                                           Homopolymer                                                                            140  351  -- --                                      Ex. 5                                                                         Comp.                                                                             B.sub.1                                                                           1.5 (60/40)                                                                           1.5 (60/40)                                                                            105   .sup. 300/*.sup.3                                                                 250                                                                              45                                      Ex. 7                         315                                             Ref.                                                                              *2  (100/0) PATE      85  285  238                                                                              30                                      Ex.             homopolymer                                                   __________________________________________________________________________              Crystallinity ·                                                      melt stability                                                                          Collection rate                                                     (400° C./10 min)                                                                 of polymer (%)                                                      Tmc  ΔHmc                                                                         Screen opening                                                                         Collect-                                                   (°C.)                                                                       (J/g)                                                                              150 μm                                                                         75 μm                                                                           ability                                                                            Remark                                      __________________________________________________________________________    Ex. 1     241  43   88  --   Excellent                                                                          Production                                                                    process                                                                       No. 1                                       Ex. 2     260  30   --  --   Good Production                                                                    process                                                                       No. 1                                       Ex. 3     246  45   80  --   Excellent                                                                          Production                                                                    process                                                                       No. 2                                       Comp.     313  55   0   0    Poor Fine powder                                 Ex. 1                                                                         Comp.     --   --   58  --   Good PATE alone                                  Ex. 2                             collected as                                                                  granules                                    Comp.     --   --   0   0    Poor Offensive odor.                             Ex. 3                             Poor copoly-                                                                  merizability                                Comp.     --   --   0   0    Poor Offensive                                   Ex. 4                             odor                                        Comp.     --   --   0   0    Poor Fine powder                                 Ex. 5                                                                         Comp.     220  38   78  --   Excellent                                                                          Block                                       Ex. 7                             copolymer                                   Ref.      218  25   --  --   --   Granular                                    Ex.                                                                           __________________________________________________________________________     Note:                                                                         *.sup.1 : Determined by DSC at a heating rate of 10° C./min by         using a quenchpressed sheet (pressed at 380° C.) as a sample.          *2: "FORTRON #W214", trade mark; poly(pphenylene thioether) produced by       Kureha Chemical Industry Co., Ltd.                                            *.sup.3 : A plurality of peaks corresponding to its melting points were       observed.                                                                

EXAMPLE 4 Solubility of Polymers in Solvent

Copolymer C₁, Block Copolymer B₁ synthesized in Comparative Example 7,PTK Homopolymer R₁ synthesized in Comparative Example 1 andpoly(p-phenylene thioether) ("FORTRON #W214", trade mark; product ofKureha Chemical Industry Co., Ltd.) were separately hot-pressed and thencooled to form amorphous sheets. The respective amorphous sheets wereplaced in the solvents shown in Table 2 to investigate their dissolutionbehavior.

As given in Table 2, Copolymer C₁ have solubility characteristicsdifferent from the PTK homopolymer and poly(p-phenylene thioether) whichare homopolymers of the components of the copolymer, and the PATE-PTKblock copolymer. After each of the polymers was dissolved in ap-chlorophenol/1,2,4-trichlorobenzene mixed solvent at 230° C., thesulfur content of the precipitate from the solution was determined. As aresult, it was found that with respect to Copolymer C₁ according to thisinvention, there is no great difference between the original polymerbefore the dissolution and that precipitated from the solution.Regarding Block Copolymer B₁ on the other hand, the sulfur content ofthe precipitate was more than that of the original polymer before thedissolution by several percent. Namely, it is understood that CopolymerC₁ according to this invention is uniform in composition distributioncompared with Block Copolymer B₁.

                                      TABLE 2                                     __________________________________________________________________________                Solvent                                                                       98% conc.         p-Chlorophenol/1,2,4-trichlorobenzene                       sulfuric acid                                                                        d-Chloronaphthalene                                                                      mixed solvent (50/50 weight ratio)                          Dissolution temperature                                                       Room   Room       Room       230° C.*.sup.2                                                                 230° C.*.sup.3        Polymer     temperature*.sup.1                                                                   temperature                                                                          225° C.                                                                    temperature                                                                          220° C.                                                                    → room temp.                                                                   → 150°         __________________________________________________________________________                                                     C.                           Copolymer C.sub.1                                                                         ◯                                                                        X      ◯                                                                     X      ◯                                                                     Gradually                                                                             ◯                                                         precipitated                         Block Copolymer B.sub.1                                                                   X      X      X   X      ◯                                                                     Precipitated                                                                          ◯                PTK Homopolymer R.sub.1                                                                   ◯                                                                        X      X   X      ◯                                                                     ◯                                                                         ◯                Poly(p-phenylene                                                                          X      X      ◯                                                                     X      ◯                                                                     X       X                            thioether)                                                                    __________________________________________________________________________     X: Insoluble,                                                                 ◯: Soluble.                                                       *.sup.1 : State when a solubilizing operation was conducted at room           temperature for 30 minutes.                                                   *.sup.2 : State when maintained at room temperature for 2 hours after a       solubilizing operation was conducted at 230° C. for 30 minutes.        *.sup.3 : State when maintained at 150° C. for 1 hours after a         solubilizing operation was conducted at 230° C. for 30 minutes.   

EXAMPLE 5 Production Process No. 1 Synthesis of PATE Oligomer

A titanium-lined reactor was charged with 127.9 g of hydrated sodiumsulfide (water content: 39.13 wt. %), 110.2 g of PDCB, 3.0 g of sodiumhydroxide and 500 g of NMP. After the reactor being purged with nitrogengas, the contents were heated to react them at 230° C. for 4 hours andthen at 240° C. for 2 hours (PDCB/sodium sulfide=0.75 mol/mol; watercontent/NMP=5.6 mol/kg), thereby obtaining a reaction slurry (Slurry S₅)containing an oligomer (Oligomer P₅) of PPTE. The amount of PDCBremaining in the reaction slurry was lower than 0.1 wt. %. Thenumber-average polymerization degree of Oligomer P₅ was 8.

Synthesis of Copolymer

A titanium-lined reactor was charged with 488 g of the resultingReaction Slurry S₅, 63.4 g of DCBP, 278 g of NMP, 18.9 g of water and16.4 g of hydrated sodium sulfide (water content: 53.98 wt. %). Afterthe reactor being purged with nitrogen gas, the contents were heated to265° C. at which they were reacted for 0.5 hour. After the contentsbeing allowed to cool down to 240° C., a final treatment of the reactionwas conducted. The final stabilizing treatment of the reaction waseffected by putting under pressure a mixture of 7.5 g of DCBP, 43 g ofNMP and 4.3 g of water in the reaction mixture to react them at 240° C.for 0.5 hour. The reaction conditions upon synthesis of the copolymerwere as follows:

(1) The molar ratio of the total amount of the charged dihalogenatedaromatic compound to the total amount of the charged alkali metalsulfide was 0.99.

(2) The molar ratio of the amount of the charged PDCB to the amount ofthe charged DCBP was 2.

(3) The ratio of the water content to the amount of the charged NMP was5.6 mol/kg.

Collection of Copolymer

Collection was conducted in the same manner as in Example 1, therebyobtaining a copolymer (Copolymer C₅). The collection rate was 70% whenrecovered by means of a screen having an opening size of 150 μm.

Physical Properties of Copolymer

The physical properties of Copolymer C₅ were as follows:

Melt viscosity: 70 poises

Transition temperature:

Tg: 112° C. (as to quench-pressed sheet)

Tm: 315° C. (as to polymer as polymerized)

Tm: 302° C. (as to quench-pressed sheet)

Melt crystallization temperature:

Tmc (400° C.): 260° C.

Tmc (400° C./10 min): 220° C.

Melt crystallization enthalpy:

ΔHmc (400° C.): 47 J/g

Residual melt crystallization enthalpy:

ΔHmc (400° C./10 min): 31 J/g

Incidentally, the weight ratio of the sum of PATE recurring units to thesum of PTK recurring units was 0.99.

EXAMPLE 6 Production Process No. 2 Synthesis of PATE Oligomer

A reaction slurry (Slurry S₆) containing a PPTE oligomer (Oligomer P₆,number-average polymerization degree: 8) was obtained in a similarmanner to Example 5.

Synthesis of PTK Oligomer

A titanium-lined reactor was charged with 101.6 g of DCBP, 4.0 g ofhydrated sodium sulfide (water content: 53.78 wt. %), 42.6 g of waterand 444 g of NMP. After the reactor being purged with nitrogen gas, thecontents were heated to 220° C. at which they were reacted for 1 hour(water content/NMP=5.6 mol/kg) to obtain a reaction slurry (Slurry KS₆)containing a PTK oligomer (Oligomer K₆). A portion of Reaction SlurryKS₆ was treated in the same manner as in Example 3 to determine thereduced viscosity of the oligomer sample. The reduced viscosity wasextremely low and the value was lower than 0.05 dl/g.

Synthesis of Copolymer

A titanium-lined reactor was charged with 587.0 g of Reaction Slurry S₆and 296.1 g of Reaction Slurry KS₆. After the reactor being purged withnitrogen, the contents were heated to 265° C. at which they were reactedfor 0.5 hour.

After the contents being allowed to cool down to 240° C., a finaltreatment of the reaction was conducted. The final stabilizing treatmentof the reaction was effected by putting under pressure a mixture of 8.0g of DCBP, 46 g of NMP and 4.6 g of water in the reaction mixture toreact them at 240° C. for 0.5 hour. The reaction conditions uponsynthesis of the copolymer were as follows:

(1) The molar ratio of the total amount of the charged dihalogenatedaromatic compound to the total amount of the charged alkali metalsulfide was 0.99.

(2) The molar ratio of the amount of the charged PDCB in the first stepto the amount of the charged DCBP in the second step was 2.9.

(3) The ratio of the water content to the amount of the charged NMP was5.6 mol/kg.

Collection of Copolymer

Collection was conducted in the same manner as in Example 1, therebyobtaining a copolymer (Copolymer C₆). The collection rate was 71% whenrecovered by means of a screen having an opening size of 150 μm.

Physical Properties of Copolymer

The physical properties of Copolymer C₆ were as follows:

Melt viscosity: 90 poises

Transition temperature:

Tg: 102° C. (as to quench-pressed sheet)

Tm: 297° C. (as to polymer as polymerized)

Tm: 294° C. (as to quench-pressed sheet)

Melt crystallization temperature:

Tmc (400° C.): 261° C.

Tmc (400° C./10 min): 214° C.

Melt crystallization enthalpy:

ΔHmc (400° C.): 54 J/g

Residual melt crystallization enthalpy:

ΔHmc (400° C./10 rain): 42 J/g

Incidentally, the weight ratio of the sum of PATE recurring units to thesum of PTK recurring units was 1.5.

EXAMPLE 7 Production Process No. 2 Synthesis of PATE Oligomer

A titanium-lined reactor was charged with 127.9 g of hydrated sodiumsulfide (water content: 39.13 wt. %), 110.2 g of PDCB, 3.0 g of sodiumhydroxide and 500 g of NMP. After the reactor being purged with nitrogengas, the contents were heated to react them at 230° C. for 6 hours andthen at 240° C. for 2 hours (PDCB/sodium sulfide=0.75 mol/mol; watercontent/NMP=5.6 mol/kg), thereby obtaining a reaction slurry (Slurry S₇)containing a PPTE oligomer (Oligomer P₇). The amount of PDCB remainingin the reaction slurry was lower than 0.1 wt. %.

The number-average polymerization degree of Oligomer P₇ was 8.

Synthesis of PTK Oligomer

A titanium-lined reactor was charged with 126.8 g of DCBP, 32.2 g ofhydrated sodium sulfide (water content: 53.98 wt. %), 38.2 g of waterand 556 g of NMP. After the reactor being purged with nitrogen gas, thecontents were heated to 220° C. at which they were reacted for 1 hour(water content/NMP=5.6 mol/kg) to obtain a reaction slurry (Slurry KS₇)containing a PTK oligomer (Oligomer K₇). A portion of Reaction SlurryKS₇ was treated in the same manner as in Example 3 to determine thereduced viscosity of the oligomer sample. The reduced viscosity wasextremely low and the value was lower than 0.05 dl/g.

Synthesis of Copolymer

A titanium-lined reactor was charged with 488.0 g of Reaction Slurry S₇and 376.8 g of Reaction Slurry KS₇. After the reactor being purged withnitrogen, the contents were heated to 265° C. at which they were reactedfor 0.5 hour. After the contents being allowed to cool down to 240° C.,a final treatment of the reaction was conducted. The final stabilizingtreatment of the reaction was effected by putting under pressure amixture of 7.5 g of DCBP, 42.8 g of NMP and 4.3 g of water in thereaction mixture to react them at 240° C. for 0.5 hour. The reactionconditions upon synthesis of the copolymer were as follows:

(1) The molar ratio of the total amount of the charged dihalogenatedaromatic compound to the total amount of the charged alkali metalsulfide wag 0.99.

(2) The molar ratio of the amount of the charged PDCB in the first stepto the amount of the charged DCBP in the second step was 2.0.

(3) The ratio of the water content to the amount of the charged NMP was5.6 mol/kg.

Collection of Copolymer

Collection was conducted in the same manner as in Example 1, therebyobtaining a copolymer (Copolymer C₇). The collection rate was 73% whenrecovered by means of a screen having an opening size of 150 μm.

Physical Properties of Copolymer

The physical properties of Copolymer C₇ were as follows:

Melt viscosity: 90 poises

Transition temperature:

Tg: 110° C. (as to quench-pressed sheet)

Tm: 314° C. (as to polymer as polymerized)

Tm: 302° C. (as to quench-pressed sheet)

Melt crystallization temperature:

Tmc (400° C.): 266° C.

Tmc (400° C./10 min): 224° C.

Melt crystallization enthalpy:

ΔHmc (400° C.): 52 J/g

Residual melt crystallization enthalpy:

ΔHmc (400° C./10 min): 38 J/g

Incidentally, the weight ratio of the sum of PATE recurring units to thesum of PTK recurring units was 0.99.

EXAMPLE 8 Production Process No. 2 Synthesis of PATE Oligomer

Reaction Slurry S₁ containing PPTE Oligomer P₁, which had been preparedin Example 1 was used.

Synthesis of PTK Oligomer

A titanium-lined 20-l reactor was charged with 1140.3 g of DCBP, 144.8 gof hydrated sodium sulfide (water content: 53.9 wt. %), 371.5 g of waterand 4995 g of NMP. After the reactor being purged with nitrogen, thecontents were maintained at 220° c for 1 hour to react them (watercontent/NMP=5 mol/kg), thereby obtaining a reaction slurry containing aPTK oligomer.

A portion of the reaction slurry thus obtained was treated in the samemanner as in Example 3 to determine the reduced viscosity of theoligomer sample. The reduced viscosity was extremely low and the valuewas lower than 0.05 dl/g.

Synthesis of Copolymer

A charge pot equipped with a heater was mounted on the titanium-linedreactor with the reaction slurry containing the PTK oligomer(temperature of slurry: 180° C.). The pot was charged with 9039 g of thereaction slurry containing the PATE oligomer. The PATEoligomer-containing reaction slurry was heated to 180° C. and then addedto the PTK oligomer-containing reaction slurry. Further, 1242 g of waterwas added, and the contents were then mixed.

The contents were maintained at 265° C. for 30 minutes to react them.After the contents being allowed to cool down to 240° C., a finaltreatment of the reaction was conducted. The final stabilizing treatmentof the reaction was effected by adding 137 g of DCBP and 776 g of NMPand then reacting the contents at 240° C. for 30 minutes. The reactionconditions upon synthesis of the copolymer were as follows:

(1) The molar ratio of the total amount of the charged dihalogenatedaromatic compound to the total amount of the charged alkali metalsulfide was 0.99.

(2) The molar ratio of the amount of the charged PDCB to the amount ofthe charged DCBP was 2.0.

(3) The ratio of the water content to the amount of the charged NMP was10 mol/kg.

Collection of Copolymer

Collection was conducted in the same manner as in Example 3, therebyobtaining a copolymer (Copolymer C₈). The collection rate was 82%.

Physical Properties of Copolymer

The physical properties of Copolymer C₈ were as follows:

Melt viscosity: 250 poises

Transition temperature:

Tg: 112° C. (as to quench-pressed sheet)

Tm: 313° C. (as to polymer as polymerized)

Tm: 297° C. (as to quench-pressed sheet)

Melt crystallization temperature:

Tmc (400° C.): 265° C.

Tmc (400° C./10 min): 234° C.

Melt crystallization enthalpy:

ΔHmc (400° C.): 49 J/g

Residual melt crystallization enthalpy:

ΔHmC (400° C./10 min): 38 J/g

Incidentally, the weight ratio of the sum of PATE recurring units to thesum of PTK recurring units was 1.0.

EXAMPLE 9 Production Process No. 1 Synthesis of PATE Oligomer

A titanium-lined reactor was charged with 127.9 g of hydrated sodiumsulfide (water content: 39.13 wt. %), 103 g of PDCB, 3.0 g of sodiumhydroxide, 20 g of water and 700 g of NMP. After the reactor beingpurged with nitrogen gas, the contents were heated to react them at 230°C. for 4 hours and at 240° C. for 2 hours (PDCB/sodium sulfide=0.70mol/mol; water content/NMP=5.6 mol/kg), thereby obtaining a reactionslurry (Slurry S₉) containing Oligomer P₉. The number-averagepolymerization degree of Oligomer P₉ was 7. The amount of PDCB remainingin the reaction slurry was lower than 0.1 wt. %.

Synthesis of Copolymer

A titanium-lined reactor was charged with 477 g of Reaction Slurry S₉thus obtained and 36.2 g of DCBP. After the reactor being purged withnitrogen gas, the contents were heated to 265° C. at which they werereacted for 0.5 hour (water content/NMP=5.6 mol/kg).

After the contents being allowed to cool down to 240° C., a finaltreatment of the reaction was conducted. The final stabilizing treatmentof the reaction was effected by putting under pressure a mixture of 5.0g of DCBP and 40 g of NMP in the reaction mixture to react them at 240°C. for 0.5 hour. The reaction conditions upon synthesis of the copolymerwere as follows:

(1) The molar ratio of the total amount of the charged dihalogenatedaromatic compound to the total amount of the charged alkali metalsulfide was 0.99.

(2) The molar ratio of the amount of the charged PDCB to the amount ofthe charged DCBP was 2.4.

(3) The ratio of the water content to the amount of the charged NMP was5.6 mol/kg.

Collection of Copolymer

Collection was conducted in the same manner as in Example 1, therebyobtaining a copolymer (Copolymer C₉). The collection rate was 78% whenrecovered by means of a screen having an opening size of 150 μm.

Physical Properties of Copolymer

The physical properties of Copolymer C₉ were as follows:

Melt viscosity: 100 poises

Transition temperature:

Tg: 106° C. (as to quench-pressed sheet)

Tm: 301° C. (as to polymer as polymerized)

Tm: 296° C. (as to quench-pressed sheet)

Melt crystallization temperature:

Tmc (400° C.): 269° C.

Tmc (400° C./10 rain): 220° C.

Melt crystallization enthalpy:

ΔHmc (400° C.): 55 J/g

Residual melt crystallization enthalpy:

ΔHmc (400° C./10 min): 43 J/g

Incidentally, the weight ratio of the sum of PATE recurring units to thesum of PTK recurring units was 1.2.

We claim:
 1. A process for the production of a poly(arylenethioether-ketone) copolymer comprising (A) at least one poly(arylenethioether-ketone) segment and (B) at least one poly(arylene thioether)segment, which comprises at least the following two steps:i) heating inthe presence of water an organic amide solvent containing adihalogenated aromatic compound, which consists principally of adihalobenzene, and an alkali metal sulfide, whereby a poly(arylenethioether) oligomer having at least 50 wt. % recurring units of theformula ##STR28## and at least one terminal thiolate group issynthesized, and ii) mixing the oligomer, which has been obtained in thestep i), with a dihalogenated aromatic compound consisting principallyof at least one dihalobenzophenone selected from4,4'-dichlorobenzophenone and 4,4'-dibromobenzophenone, and optionally,an alkali metal sulfide, an organic amide solvent and/or water, andheating the resultant mixture to form a poly(arylene thioether-ketone)segment having at least 50 wt. % recurring units of the formula##STR29## wherein the --CO-- and --S-- are in the para position to eachother, thereby forming the copolymer; said first and second steps i) andii) being conducted under the following conditions (a)-(f):(a) in thefirst step i), the ratio of the water content to the amount of thecharged organic amide solvent being 0.1-15 (mol/kg), the ratio of theamount of the charged dihalogenated aromatic compound to the amount ofthe charged alkali metal sulfide being 0.3-0.9 (mol/mol), and thepolymerization being conducted in such a manner that the resultingpoly(arylene thioether) oligomer has at least one terminal thiolategroup and its number-average polymerization degree becomes higher than 1but lower than 10, (b) in the second step ii), the ratio of the watercontent to the amount of the charged organic amide solvent beingcontrolled within a range of 0.1-15 (mol/kg), (c) in the second stepii), the ratio of the total amount of the charged dihalogenated aromaticcompound, said total amount being the amount of the whole dihalogenatedaromatic compounds including the dihalobenzene and thedihalobenzophenone, to the total amount of the charged alkali metalsulfide, said latter total amount being the total amount of the alkalimetal sulfide charged in the first step i) and that optionally chargedin the second step ii), being controlled within a range of 0.95-1.2(mol/mol), (d) the ratio of the charged amount of the dihalogenatedaromatic compound consisting principally of the dihalobenzene in thestep i) to the charged amount of the dihalogenated aromatic compoundconsisting principally of the dihalobenzophenone in the step ii) beingcontrolled within a range of 0.1-10 (mol/mol), (e) the reaction of thesecond step ii) being conducted within a temperature range of 150°-300°C. with the proviso that the reaction time at 210° C. and higher is notlonger than 10 hours, and (f) in the second step ii), the reaction beingconducted until the melt viscosity of the resulting copolymer becomes2-100,000 poises as measured at 350° C. and a shear rate of 1,200/sec.2. The process as claimed in claim 1, wherein the poly(arylenethioether) oligomer has at least 50 wt. % recurring units of the formula##STR30##
 3. The process as claimed in claim 1, wherein in each of thesteps i) and ii), the reaction is conducted in a reactor at least aportion of which, said portion being brought into contact with thereaction mixture, is made of a corrosion-resistant material.
 4. Theprocess as claimed in claim 3, wherein the corrosion-resistant materialis a titanium material.
 5. The process as claimed in claim 1, whereinthe organic amide solvent is at least one pyrrolidone selected fromN-methylpyrrolidone and N-ethylpyrrolidone.
 6. The process as claimed inclaim 1, wherein upon obtaining the poly(arylene thioether-ketone)copolymer, at least 50 wt. % of the resulting copolymer is in the formof granules recoverable on a sieve having an opening size of 75 μm.